this thursday vice president joe biden will trade opinions in foreign and domestic policy with g-o-p vice presidential candidate paul ryan in the vice presidential debate. the final two presidential debates will air live on october 16th and 22nd. this week we spoke to an expert on presidental debates...he outlines the history of this american political tradition. ">>>this week the american people had a chance to see both canidates side by side as they told voters why they should be the president of the united states. how much effect will the debates have on the vote? "i think that they can the political science literature suggests that they don't have a great amount of impact on the election but i really think that they can they help drive the narrative." political science professor james brent says debates have not been very memorable in the past few elections. past presidential debates had any dramatic moments that helped shape the race? mit romney is trailing in the polls so what might we expect from him? "mit romney wants to do a couple of things humanize himself he seams aloof a